Device for separating materials held in suspension by liquids.



PATENTED NOV. 26, 1907.

0. N. WAITB. DEVICE FOR SEPARATING MATERIALS HELD IN SUSPENSION BYLIQUIDS.

APPLICATION FILED APR. 7, 1906.

FICiI.

WITNESSES: $6 6 UNITED STATES PATENT OFFICE.

CHARLES N. WAITE, OF WILMINGTON, DELAWARE.

DEVICE FOR SEPARATIN G MATERIALS HELD IN SUSPENSION BY LIQUIDS.

Specification of Letters Patent.

Patented Nov. 26, 1907.

Application filed April 7. 1906. Serial No. 310.420.

To all whom it may concern:

Be it known that I, CHARLES N. WAITE, of Wilmington, Delaware, haveinvented certain new and useful Improvements in Devices for Se aratingMaterial .Held in Suspension by iquids, whereof the following is aspecification, reference being had to the accomlpanying drawings.

T e primary application of my invention relates to the devices known asulp-savers,

the object of which is to remove t eisolid and flocculent material fromthe so called white water of paper mills,- and I will therefore explainthe invention in connection with an apparatus specifically addressed tothat purpose.

' In the accompanying drawings, Figure I,

represents a vertical section through the main portion of the a paratusshowing adj acent parts in side e evation. Fig. II, is a fragmentaryelevational view of the controllingmechanism looking toward the right inFig. I.

The apparatus comprises a receiving tank 1 the lower portion of which ispreferably tapered as indicated at 2. The pipe 3, for the admission ofthe white water enters the tank laterally and discharges downwardscentrally therein at about the level where the taper of the bottombegins. Beneath the discharge orifice a distributor 4, preferablyconical may be arranged, said distributor being conveniently su portedby means of legs 5, secured to the si es of the tank.

Some distance below the top of the tank is a transverse screen 6, ofwiregauze or other suitable material, which for use with ordinary whitewater should be of about seventy mesh. A discharge pipe 7, is arrangedabove the-screen preferably at such a level as to maintain a substantialdepth of water thereover as indicated at 8, thus affording a back flowdownwards through the screen under the conditions hereinafter set forth.

At the apex of the ta 'ered bottom of the receiving tank, is an out etipe 9, for the collected residue of se arated material, which pi isrovided wit a centrifugal pump 10, W ose elivery pipe 11, leads toanyconvenient int. Said centrifugal pump is actuated y means of the belt12, arranged in the ordinaryrelation to fast and loose pulleys 13,

'and 14. A belt shifter 15, is actuated by through the link 18, saidlever arm may be conveniently fulcrumed at 19, u on a collar 20, securedto the vertical leg of t e discharge pipe 11. The other end 21, of thelever 17, is connected with a float 22, which is disposed within a smallsecondary tank 23, supported above the level of the receiving tank 1 andcommunicating therewith by means of a pipe 24, whose orifice is somedistance below the level of'the diaphragm '6. This ipe is controlled bymeans of a valve 25, wliich can be set so as to reduce the effectivearea of the ipe to any desired degree.

Tfie operation of the device is as follows Assuming that the whitewater, containing the pulp to be separated, isdelivered through the pipe3, in a substantially regular stream, and at a moderate rate, the effectof the distributer 4, is to cause the settling of the solid andfiocculent material in a quiet and uniform manner, Without seriousdisturbance of the material previously deposited. As the white waterrises in the receiving tank, it reaches the diaphragm 6, and thesuspended portions of the flocculent material are caught by the wiregauze and remain on the under side thereof. The water which filtersthrough the wire gauze is comparatively free from the solid material andflows out through the pipe 7. As however, the operation progresses, themeshes of the diaphragm 6, become clogged by the accumulation of thefiocculent material upon the under side, and when this clogging hasextended entirely across the diaphragm, the efficiency of, the apparatusof course becomes impaired, as substantial outflow can no longer-takeplace, and the inflow continues. The effect is to create a pressure inthat portion of the receivingtank which is beneath the diaphragm 6,anriv'fihis pressure causes the water to rise the pipe 24 (the valve 25being set tqfleaye any desired area of opening) into the" secondary.tank 23, where it accumulates" raises the float 22. During all thistime, the belt 12, has been upon the loose pulley and the pump 10, hasbeen idle. The rise of the float however acv tuates the lever 17 andhell crank 16, so as to shift the belt ,l2 ,g fre zp the loose pulleyonto the fast pulley} ifiiereupon, the pump IQ, is actuated towitligdraw the separated residue of material from the bottom 2, of thetank -1. As this action rogresses, the level of the liquid contents 0'the receiving tank eration.

falls, and a back flow of water takes place from above the screen, whichwill wash the material downwards and clear the meshes of the gauze,since the clogging material is practically all upon the lower side.

' Owing to the fact that the orifice controlled by the valve 25, isproperly set to prevent the rapid outflow of water from the secondarytank 23, the pumping out of material from the receiving tank 1, andconse uent relief of pressure, will not be immediate y attended by thecomplete dischar e of the water in the tank 23, sothat the oat 22, mayremain in the position corresponding with the actuation of the pump forsome little time after the water level has fallen in the tank 1.Ultimately, however, the pressure beneath the diaphragm being relieved,the,

permit the automatic operation of the apparatus, not merely in order todischarge the accumulated material, but to maintain the conditions whichare eflicient forseparation.

From the principle of operation above described, it will be observedthat it depends upon the presence, in the receiving tank, of an element,(which may broadly be termed a screen) throughwhich the liquid passes tothe point of overflow, and upon the fact that when this screen becomesclogged, it can be cleansed by a back-flow of liquid, automaticallycontrolled. In the embodiment above described, the pressure created inthe region below the screen is utilized to initiate the automaticoperation, but obviously the essence of the invention does not dependupon such a method of affording the desired control, and hence I do notlimit my broad claim to the described organization. I

would also state that the screen element shall be as extended aspossible, and therefore it is'shown as composed of gauze across theentire area of the tank. It is, however, obvious that a portion of itmight be solid,

- the only essential condition being that the screen shall be efiicientto prevent substantial escape of recoverable material, and shall beaccessible to the back flow of liquid when clogging takes place.

Having thus described my invention, I claim:

1. In a separating device, the combination with a tank; of a screendividing said tank; an inlet pipe for unseparated materials, arranged onone side of said screen; an outlet for separated residue arranged uponthe same side of said screen; an outlet for strained liquid, arranged onthe opposite side of said screen; means for efiecting the discharge ofthe separated residue; and means responsive to abnormal increase ofpressure beneath the screen for actuating the controlling mechanism ofsaid discharging means.

2. In a separating device, the combination with a receiving tank; of ascreen dividing said tank; an inlet ipe for unseparated materials,arranged be ow the screen; an

outlet for separated residue, also arranged below said screen; an outletfor strained liquid arranged above said screen; a pump connected withthe outlet for separated residue; actuating mechanism for said pump; a

evel

secondary tank arranged at a higher than the normal water level of themain I tank; a float arranged said secondary tank; and means operativelyconnected with said float for controlling the actuating mechanism of thepump.

3.- In a separating device, the combination with a receiving tank; of ascreen dividsaid tank; an inlet pipe for unseparated materials, arrangedbelow the screen; an outlet for separated residue, also arranged belowsaid screen; an outlet for strained li uid arranged above said screen,and adapte to maintain a body of liquid at the maximum water level ofthe receiving tank; a pump connected with the outlet for separatedresidue; actuating mechanism for said um a secondary tank arranged at ahigher l evel than the normal water level of the main tank; a, floatarranged in said secondary tank; and means operatively connected withsaid float forgcontrolling the actuating mechism of the pump.

CHARLES N. WAITE.

Witnesses:

JAMES H. BELL, E. L. FULLERTON.

